Mismatch between classroom furniture and anthropometric measures in Chilean schools

Children spend about five hours per day sitting down while doing their school work. Considering this as well as the potential inadequate use of school furniture, it is likely that some anatomical-functional changes and problems in the learning process may occur. The aim of this study was to compare furniture sizes within three different schools with the anthropometric characteristics of Chilean students in the Valparaíso region, in order to evaluate the potential mismatch between them. The sample consisted of 195 volunteer students (94 male, 101 female) of the 8th grade, ranging from 12.5 to 14.5 years of age from 3 different schools. Regarding the methodology, 6 anthropometric measures (Stature, Popliteal height, Buttock-popliteal length, Elbow height while sitting, Hip width, Thigh thickness and Subscapular height) were gathered, as well as 8 dimensions from the school furniture. For the evaluation of classroom furniture a match criterion equation was defined. After considering the existing classroom furniture dimensions in each match criterion equation, the anthropometric characteristics of the considered population were compared in order to determine the mismatch between them. Results indicated that seat height, which should be considered as the starting point for the design of classroom furniture, was appropriate for students' popliteal height in only 14% of the 2 out of the 3 schools, and 28% in the third. Seat to desk height was too high and mismatched 99% of the students in one school and 100% in the others. Therefore, it was possible to conclude that the classroom's furniture was inadequate in almost all the analyzed cases and subjects. It is possible that the high mismatch percentage found between furniture and students' anthropometry can be associated to the fact that the acquisition and selection of the furniture was made without any ergonomic concern or criteria.     

Equations for defining the mismatch between students and school furniture: A systematic review

The present study reviews the scientific literature that describes the criteria equations for defining the mismatch between students and school furniture. This mismatch may negatively affect students' performance and comfort. Seventeen studies met the criteria of this review and twenty-one equations to test six furniture dimensions were identified. There was substantial mismatch between the relative heights of chairs and tables. Some systematic errors have been found during the application of the different equations, such as the assumption that students are sitting on chairs with a proper seat height. Only one study considered the cumulative fit. Finally, some equations are based on contradictory criteria and need to develop and evaluate new equations for these cases.Relevance to industryUltimately, the present work is a contribution toward improving the evaluation of school furniture and could be used to design ergonomic-oriented classroom furniture.     

Applying different equations to evaluate the level of mismatch between students and school furniture

The mismatch between students and school furniture is likely to result in a number of negative effects, such as uncomfortable body posture, pain, and ultimately, it may also affect the learning process. This study's main aim is to review the literature describing the criteria equations for defining the mismatch between students and school furniture, to apply these equations to a specific sample and, based on the results, to propose a methodology to evaluate school furniture suitability. The literature review comprises one publications database, which was used to identify the studies carried out in the field of the abovementioned mismatch. The sample used for testing the different equations was composed of 2261 volunteer subjects from 14 schools. Fifteen studies were found to meet the criteria of this review and 21 equations to test 6 furniture dimensions were identified. Regarding seat height, there are considerable differences between the two most frequently used equations. Although seat to desk clearance was evaluated by knee height, this condition seems to be based on the false assumption that students are sitting on a chair with a proper seat height. Finally, the proposed methodology for suitability evaluation of school furniture should allow for a more reliable analysis of school furniture.     

Sex differences in anthropometry for school furniture design

This paper is concerned with anthropometric dimensions of young Koreans and their interrelationships for school furniture design. Ten anthropometric measurements were taken from 1248 subjects, age range 6-17. The study investigated sex differences in interrelationships between body dimensions, to provide suitable sizes of chair and desk for boys and girls. The results showed that stature had a high relationship to body dimensions for school furniture design, and that there were significant sex differences in relationships between stature and the body dimensions. In particular, boys above 126 cm in stature required higher desk and chair heights than girls of the same stature. On the other hand, girls above 120 cm in stature required a larger depth and breadth of chair than boys of the same stature.     

Evidence for the need to update the Chilean standard for school furniture dimension specifications

Some countries decide to use standards to define the type of furniture dimensions that should be used according to students' anthropometric characteristics. The aim of this paper is to generate data to update the standard for Chilean school furniture using student anthropometric data. The sample used involved 3078 students. Data collection included eight anthropometric dimensions. A strict procedure was followed to define six furniture school dimensions. The definition of the compatibility between students' characteristics and furniture dimensions was done using the concept of mismatch computed through a set of equations. The results showed differences in mismatch levels between the two compared approaches, with lower mismatch found using the new proposed approach – the updated standard (UpS). Seat depth presents the greatest difference in mismatch, with values of 43% for the current Chilean standard (ChS) and 17% for the UpS. Also, seat height match values are almost the same (100%); however, it is important to mention that the level of match could drop to 82% in the ChS if the furniture selection was already carried out, as suggested in the standard itself, by using the Stature. Finally the UpS presents a higher covered range in the six furniture dimensions. The obtained results reflect the need to update the data and the procedure for school furniture selection presented by the current Chilean standard. Relevance for industry: this paper presents relevant data to be used by both school furniture designers, as well as by those responsible for the furniture selection at schools. In addition, proof is presented that school furniture standards need to be updated periodically in order to better fit the students’ anthropometric characteristics.     

Anthropometrics for the design of Bahraini school furniture

This paper presents the results of an anthropometric survey carried out on a sample of male and female Bahraini school children aged 6–12 years (N = 1174), to throw some light on the anthropometric parameters of Bahraini students in order to provide school furniture designers and importers with relevant data. A set of 44 body dimensions covering most body parts were measured, from which six body dimensions relevant to school furniture design were considered. Results show a gradual increase from age 6 to age 12 in all body dimensions. When compared with children from other nationalities, Bahraini children were almost all of medium height and weight. This paper also shows how the results can be used in school furniture design.

Relevance to industry

The 21st century has seen a lot of interest in children, especially school children as it is well known that many postural problems, such as back pain and repetitive strain injuries, start at an early age. Therefore, ergonomics design for children is as important as designing for adults. Anthropometric data are essential for this design.     

Neural network and multiple linear regression to predict school children dimensions for ergonomic school furniture design

The current study investigates the possibility of obtaining the anthropometric dimensions, critical to school furniture design, without measuring all of them. The study first selects some anthropometric dimensions that are easy to measure. Two methods are then used to check if these easy-to-measure dimensions can predict the dimensions critical to the furniture design. These methods are multiple linear regression and neural networks. Each dimension that is deemed necessary to ergonomically design school furniture is expressed as a function of some other measured anthropometric dimensions. Results show that out of the five dimensions needed for chair design, four can be related to other dimensions that can be measured while children are standing. Therefore, the method suggested here would definitely save time and effort and avoid the difficulty of dealing with students while measuring these dimensions. In general, it was found that neural networks perform better than multiple linear regression in the current study.     

Sex differences in anthropometry for school furniture design

This paper is concerned with anthropometric dimensions of young Koreans and their interrelationships for school furniture design. Ten anthropometric measurements were taken from 1248 subjects, age range 6-17. The study investigated sex differences in interrelationships between body dimensions, to provide suitable sizes of chair and desk for boys and girls. The results showed that stature had a high relationship to body dimensions for school furniture design, and that there were significant sex differences in relationships between stature and the body dimensions. In particular, boys above 126 cm in stature required higher desk and chair heights than girls of the same stature. On the other hand, girls above 120 cm in stature required a larger depth and breadth of chair than boys of the same stature.     

School furniture and the user population: an anthropometric perspective

The purpose of this study was to determine the relationship between reported spinal symptoms in an adolescent student population, and the match between their individual anthropometric dimensions and their school furniture. The hypothesis was that students who were too large or too small for their school furniture, i.e. with anthropometric measurements furthest from the group whose anthropometry was the ‘best fit’ with the furniture, would have a higher frequency of reported symptoms. From data collected from 1269 schoolchildren, reported spinal symptoms and anthropometric measures were examined. Stature measures were divided into quartiles. A standard government issue school chair and desk was measured and the anthropometric quartile of the population having the ‘best fit’ with the furniture was identified using standard ergonomics recommendations. Odds ratios were calculated for spinal symptoms reported within each quartile group. The first quartile group (the smallest students) was identified as having the ‘best fit’ with the school furniture. An overall higher odds of reporting low back pain was noted in students with anthropometric dimensions in the fourth quartile (the tallest students). While it is acknowledged that there is a multifactorial nature of causality of adolescent spinal symptoms, it is contended that the degree of mis-match between child anthropometry and school furniture set-up should be further examined as a strong and plausible associate of adolescent low back pain.     

A comparative study of three different kinds of school furniture

Abstract

Several studies indicate that the ISO standards for school furniture seem to be inappropriate, and there is increasing evidence that the inclination of the seat should be forward and that it should be possible to adjust the table-top to a certain non-horizontal angle. However, these studies have predominantly used objective measurement methods on adult subjects for short-term experiments in rather artificial surroundings. By means of structured interviews registering the school children's perception of ergonomic comfort, the present study has compared three types of school furniture—the original ISO-standard type, and two different new types characterized by forward slanting seats and tiltable desk-tops, the main difference between the two being approximately 15 cm in the height of the chair as well as the table. The study showed that the highest of the two tilting types was perceived to be significantly better than the two others in terms of table height, chair height, reading position, back-rest, and global assessment. Likewise, the feature of a tiltable table-top was considered overwhelmingly positive independently of the height of the furniture. It is recommended that school authorities, producers of school furniture, and relevant medical personnel consider these results for alternative designs of school furniture. It should be kept in mind, however, that school furniture is only one among many factors in the multifactorial field of the back health of school children.     

Classroom furniture dimensions and anthropometric measures in primary school

The purpose of this study was to compare students' dimensions to the dimension of school furniture, in primary school, and determine whether this type of furniture is well-designed and promotes good sitting posture at school by taking into account the dimensions of the children. A total of 180 (90 male and 90 female) students, from three primary schools in Thessaloniki, Greece, participated in the study. Their ages ranged from 7 to 12 years. The following human body dimensions were measured: stature, elbow height, shoulder height, upper arm length, knee height, popliteal height and buttock-popliteal length. In addition, the dimensions were measured for four different types of chairs and five types of desks prevalent in classrooms. Finally, the anthropometric measures of the students and the furniture dimensions were compared in order to identify any incompatibility between them. The data indicate a mismatch between the students' bodily dimensions and the classroom furniture available to them. The chairs are too high and too deep and desks are also too high for the pupils. This situation has negative effects on the sitting posture of the children especially when reading and writing.     

The relationship between anthropometry and hand grip strength among elderly Malaysians

It is known that the ageing process will result in a decrease in anthropometric dimensions as well as loss of hand grip strength, which is natural among elderly people. Previous studies have shown that the decrease in anthropometric dimensions may influence hand grip strength of elderly people. Hence, this paper seeks to determine the relationship between anthropometric dimensions and hand grip strength among elderly Malaysians. A total of 112 elderly subjects aged 60 years and above residing in Petaling Jaya, Selangor, are recruited in this study. The subjects comprise 56 males (age range 60–79 years, mean: 66.88, SD: 5.35) and 56 females (age range: 60–82 years, mean: 66.98, SD: 5.16). In this study, 38 anthropometric dimensions are measured, along with hand grip strength. The anthropometric dimensions are measured using a professional standard anthropometry set whereas hand grip strength (in Newtons) is measured using a dynamometer. The mean values, standard deviations and percentiles are determined and the data are analysed by correlation analysis. The results show that there is a significant correlation between the following anthropometric dimensions (stature, sitting hip breadth, wrist circumference, hand circumference and heel ankle circumference) and hand grip strength. These findings of this study are indeed useful for product designers to design and develop ergonomic hand-held products for elderly Malaysians.     

Book Review

Musculoskeletal symptoms are one of the top ten health problems among schoolchildren in Hong Kong. Whether or not these symptoms are related to school furniture has yet to be determined and published data on furniture size are lacking. The purpose of the study was to determine whether the design of furniture in schools is appropriate for children's anthropometry. A total of 214 volunteer subjects were recruited. This constituted 90% of the total number of primary 5 and 6 students in the studied school (i.e. those aged 10 and 13 years). The data collected included demographic information, data on perceived health and posture and body and furniture measurements. The girls' BMI was lower than that of the boys. The girls had longer lower limbs and wider hip breadth measurements in the standing position. This was similar in the sitting position. Almost none of the subjects had a chair with an appropriate seat height. Seat depth was found appropriate for large groups of students whether or not a large or small chair was used. Recommendations on the sizes of chairs and desks for boys and girls are discussed.     

Incorporating anthropometry into design of ear-related products

To achieve mass customization and collaborative product design, human factors and ergonomics should play a key development role. The purpose of this study was to provide product designers with the anthropometic dimensions of outer ears for different demographic data, including gender and age. The second purpose was to compare the dimensions of various ear-related products (i.e., earphone, bluetooth earphone and ear-cup earphone) with the anthropometic database and recommend appropriate solutions for design. Two hundred subjects aged 20-59 was selected for this study and divided into four age stratifications. Further, three different dimensions of the outer ear (i.e., the earhole length, the ear connection length and the length of the pinna) were measured by superimposed grid photographic technique. The analysis of variance (ANOVA) was used to investigate the effects of gender, and age on ear dimensions. The results showed that all ear dimensions had significant gender effects. A comparison between the anthropometric dimensions and those of current products revealed that most current ear-related products need to be redesigned using anthropometric data. The shapes of earhole and pinna are not circular. Consequently, ear products need to be elongated so that users may feel more comfortably and not have the product slip off easily.     

Development of an ergonomics guideline for the furniture manufacturing industry

Industry-specific ergonomics guidelines are an important component in the four-pronged approach to workplace ergonomics currently pursued by the United States Occupational Safety and Health Administration. The American Furniture Manufacturers Association has taken the initiative of developing such a guideline for its members. The result of this effort is the "AFMA Voluntary Ergonomics Guideline for the Furniture Manufacturing Industry", a document that includes basic information about ergonomics program components as well as a compilation of work-proven, ergonomics best practices as submitted by members of the furniture manufacturing community. This guideline was developed through an industry-research-government partnership and made strategic use of the unique attributes that each sector brought to this effort. Outlined in this paper are some of the characteristics of this partnership including, the roles played by each, the different motivations for pursuing the guideline, the challenges faced during the development of the document, the successes experienced in this process, as well as a proposed outline for measuring the effectiveness of this effort. The hope is that this summary, and some of the lessons learned contained herein, would be helpful to others considering the prospect of developing such a guideline for their industry.     

Lack of conformity between Indian classroom furniture and student dimensions: proposed future seat/table dimensions

Children spend one-quarter of a day in school. Of this, 60-80% of time is spent in the classroom. Classroom features, such as workspace and personal space play an important role in children's growth and performance as this age marks the period of anatomical, physiological and psychological developments. Since the classroom is an influential part of a student's life the present study focused on classroom furniture in relation to students' workspace and personal space requirements and standards and was conducted in five schools at Mumbai, India. Dimensions of 104 items of furniture (chairs and desks) were measured as were 42 anthropometric dimensions of 225 students from grade six to grade nine (age: 10-14 years). Questionnaire responses of 292 students regarding the perceived adequacy of their classroom furniture were collected. Results indicated that the seat and desk heights (450 mm, 757 mm respectively) were higher than the comparable students' anthropometric dimensions and that of the recommendations of Bureau of Indian Standards (BIS) (340 + 3 mm, 380 + 3 mm seat-heights, 580 + 3 mm 640 + 3 mm desk-heights) as well as Time-Saver Standards (TSS) (381.0 mm seat-height and 660.4 mm desk-height). The depth of the seats and the desks (299 mm, 319 mm, respectively) were less than comparable students' anthropometric dimensions and the recommendations of BIS (IS 4837: 1990). Students reported discomfort in shoulder, wrist, knee and ankle regions. Based on the students' anthropometric data, proposed future designs with fixed table-heights and adjustable seat-heights along with footrests were identified.     

School furniture match to students' anthropometry in the Gaza Strip

This study aimed at comparing primary school students' anthropometry to the dimensions of school furniture and determining whether the furniture used matches the students' anthropometry. A sample of 600 male students, whose ages were between 6 and 11 years, from five primary schools in the Gaza Strip governorates participated in the study. Several students' body dimensions were measured. The dimensions measured included elbow–seat height, shoulder height, knee height, popliteal height and buttock–popliteal length. Measurements of the dimensions of the classroom furniture indicated that there was a considerable mismatch between the students' body dimensions and the classroom furniture. The mismatches in seat height, seat depth and desk height occurred for 99% of the students, while the mismatch for the back rest height was only 35%. Two design specifications were proposed in order to decrease the mismatch percentage based on the data obtained. The two proposed designs showed a considerable improvement in the match percentages as compared to the existing design.

Statement of Relevance: Having identified mismatches between the dimensions of the school furniture used in primary schools in the Gaza Strip, two new design specifications are proposed and shown to improve match with the students' anthropometric dimensions. The findings of the study are also an important addition to local knowledge on school children's anthropometry.